This invention relates to packaging machines and more particularly to a packaging machine especially designed for packaging quantities of materials to fill individual orders and the process of filling such orders.
Machines that use webs of pre-opened bags to form packages are now well known. Such webs of bags are disclosed and claimed in the U.S. Pat. No. 3,254,828 entitled Flexible Container Strips (the Autobag Patent). A machine which is currently in wide usage commercially for forming packages from chains of pre-opened bags utilizing a novel web tensioning dancer mechanism is described and claimed in U.S. Pat. No. 5,394,676 issued Mar. 7, 1995 to Bernard Lerner et al. under the titled Packaging Machine and Method (the Excel Patent). Machines made in accordance with the teaching of the Excel Patent often are supplied parts to be packaged by modular systems of counters and/or weighers and conveyors in order that packages can be formed automatically and at relatively high speeds.
The Excel machines are often equipped with printers such as described and claimed in U.S. Pat. No. 5,371,521 issued Dec. 6, 1994 to Rick S. Wehrmann (the Teeter Totter Patent). The machine of the Teeter Totter Patent is designed to print identical information on each bag in a chain of interconnected bags. The Teeter Totter Patent is directed to a mechanism which tensions the chain of bags and feeds it past a print head in a printing section of a chain of bags. The printing section is tension isolated from a supply section which supplies the chain and also from a downstream section which delivers bags to a load station such that the three sections are independently tensioned.
The Excel Patent teaches a dancer mechanism which independently tensions the supply section upstream from the printer section while a conveyor system effects tensioning of the downstream section. These mechanisms produce the three isolated, individually tensioned sections along the feed path of an Excel machine.
Relatively large xe2x80x9cmail orderxe2x80x9d and xe2x80x9ce-businessxe2x80x9d organizations require systems for filling individual orders. An example is organizations which fill individual orders for pharmaceuticals. Such pharmaceutical organizations typically utilize so called wicketed bags for packaging individual orders for shipment offsite to customers. Pressure sensitive labels are used to identify the contents of each bag and to provide an address for shipment of each filled bag to a customer at an offsite location. The wicketed bag approach is slow and expensive. For pharmaceutical shipment it is especially expensive in that only registered pharmacists can fill individual bags with pharmaceutical orders so that each load station must have an assigned pharmacist.
A machine which is a modified version of a packaging machine competitive with the Excel machine is currently being offered for sale. This modified machine has what has been characterized as a ditch to receive and accumulate each bag in an untensioned loop after it has been printed but before it is fed to a load station. This results in printing errors and wrinkling of bags such that finished packages are not as attractive as they should be and lost shipments can result from printing errors.
Accordingly it would be desirable to provide a machine which uses a web of pre-opened bags for packaging individual orders and which prints identifying information on an upstream tensioned bag as a previously printed bag is loaded with its appropriate batch of pharmaceuticals and sealed.